The target of this thesis is to report the steps taken in the development of two ASICs: TERA and the successor SCARLET, as well as the development of a specific DAQ for both ASICs. SCARLET project aims to develop a new multichannel X-ray detector based on pixelated Silicon Drift Detector (SDD), bump-bonded with readout ASIC containing full processing electronics implemented in a single pixel. The starting point of this project is TERA (Throughput Enhanced Readout ASIC), an analog pulse processor ASIC which has demonstrated good energy resolution and high-throughput capability (>1Mcps/channel) simultaneously, comparable to conventional digital pulse processor. The motivations, challenges and requirements for this transition are high- lighted in the thesis. A detailed description is given to changes made on ASIC level, either to improve the current performance (e.g further improvement of count rate capability) or add new functionalities (e.g. Input Count Rate (ICR) estimation). A new digital acquisition (DAQ) system, compatible with both TERA and SCARLET, has been developed during this thesis. The thesis is organized as follows: Chapter 1 provides an introduction to radiation detection, Silicon Drift Detector and a brief description of detector pulse processing methods, focusing on energy resolution related issues. Chapter 2 opens with a discussion about TERA readout chip. Then, SCARLET project is introduced, outlining the motivations and the requirements for the transition from TERA. The Prototype 0, developed to evaluate the impact of the new pixel structure, is also presented. The chapter concludes with the description of the general structure of a new DAQ system developed for both TERA and SCARLET. Chapter 3 focuses on the hardware part of the DAQ system. The functionality and the design of the new custom made Printed Circuit Boards are showed and explained. Chapter 4 focuses on the VHDL firmware structure implemented for the readout. The design of the digital platform is explained in detail, as several independent sub-blocks have been developed, each of them performing one of the functions needed for acquiring and elaborating signals. Lastly, the graphical user interface developed for data acquisition is depicted. Chapter 5 describes the measurements taken for the characterization and validation of the designed platform. In the end, the thesis is closed with the suggestions for future works.
L’oggetto del seguente elaborato di tesi è di descrivere gli step compiuti nello sviluppo di due ASIC: TERA ed il successore SCARLET, nonchè lo sviluppo di uno specifico DAQ per entrambi gli ASIC. Il progetto SCARLET mira a sviluppare un nuovo rivelatore di raggi X, multicanale, basato su Silicon Drift Detector (SDD) pixelato, bump-bonded con il read-out ASIC contenente l’elettronica di elaborazione del segnale implementata in un singolo pixel. Il punto di partenza di questo progetto è TERA (Throughput Enhanced Readout ASIC), un processore analogico di impulsi che ha dimostrato simultaneamente una buona risoluzione energetica e un’alta capacità di conteggio (>1Mcps/canale), paragonabile ai processori digitali convenzionali di impulsi da rivelatori. Nella tesi vengono evidenziate le motivazioni, le sfide e i requisiti per questa transizione. Viene fornita una descrizione dettagliata delle modifiche apportate a livello dell’ASIC, sia per migliorare le prestazioni attuali (es. ulteriore miglioramento della capacità di conteggio) sia per aggiungere nuove funzionalità (es. stimare l’Input Count Rate (ICR)). Un nuovo sistema DAQ, compatibile sia con TERA che con SCARLET, è stato inoltre sviluppato nella tesi. La tesi è organizzata come segue: Il Capitolo 1 fornisce un’introduzione alla rivelazione di radiazioni, Silicon Drift Detectors, e una breve descrizione della catena di elaborazione del segnale, sottolineando le problematiche inficianti la risoluzione di energia. Il Capitolo 2 si apre con una discussione sul TERA readout chip. Quindi, viene introdotto il progetto SCARLET, delineando le motivazioni e i requisiti per il passaggio da TERA. Viene inoltre presentato il Prototipo 0, sviluppato per valutare l’impatto della nuova struttura dei pixel. Il capitolo si conclude con la descrizione della struttura generale del nuovo sistema DAQ sviluppato sia per TERA che per SCARLET. Il Capitolo 3 si concentra sulla parte hardware del sistema DAQ. Vengono mostrate e spiegate la funzionalità e il design dei nuovi circuiti stampati. Il Capitolo 4 si concentra sulla struttura del firmware VHDL implementata per la lettura. Il design della piattaforma digitale è spiegato in dettaglio, con i diversi sottogruppi indipendenti, ognuno dei quali svolge delle funzioni necessarie per l’acquisizione e l’elaborazione dei segnali. Infine viene rappresentata l’interfaccia grafica sviluppata per l’acquisizione dei dati. Il Capitolo 5 descrive le misure eseguite per la caratterizzazione e la validazione della piattaforma progettata. Alla fine, la tesi si chiude con i suggerimenti per sviluppi futuri.
From TERA to SCARLET : ASIC and DAQ upgrade for X-ray applications
Deda, Griseld
2019/2020
Abstract
The target of this thesis is to report the steps taken in the development of two ASICs: TERA and the successor SCARLET, as well as the development of a specific DAQ for both ASICs. SCARLET project aims to develop a new multichannel X-ray detector based on pixelated Silicon Drift Detector (SDD), bump-bonded with readout ASIC containing full processing electronics implemented in a single pixel. The starting point of this project is TERA (Throughput Enhanced Readout ASIC), an analog pulse processor ASIC which has demonstrated good energy resolution and high-throughput capability (>1Mcps/channel) simultaneously, comparable to conventional digital pulse processor. The motivations, challenges and requirements for this transition are high- lighted in the thesis. A detailed description is given to changes made on ASIC level, either to improve the current performance (e.g further improvement of count rate capability) or add new functionalities (e.g. Input Count Rate (ICR) estimation). A new digital acquisition (DAQ) system, compatible with both TERA and SCARLET, has been developed during this thesis. The thesis is organized as follows: Chapter 1 provides an introduction to radiation detection, Silicon Drift Detector and a brief description of detector pulse processing methods, focusing on energy resolution related issues. Chapter 2 opens with a discussion about TERA readout chip. Then, SCARLET project is introduced, outlining the motivations and the requirements for the transition from TERA. The Prototype 0, developed to evaluate the impact of the new pixel structure, is also presented. The chapter concludes with the description of the general structure of a new DAQ system developed for both TERA and SCARLET. Chapter 3 focuses on the hardware part of the DAQ system. The functionality and the design of the new custom made Printed Circuit Boards are showed and explained. Chapter 4 focuses on the VHDL firmware structure implemented for the readout. The design of the digital platform is explained in detail, as several independent sub-blocks have been developed, each of them performing one of the functions needed for acquiring and elaborating signals. Lastly, the graphical user interface developed for data acquisition is depicted. Chapter 5 describes the measurements taken for the characterization and validation of the designed platform. In the end, the thesis is closed with the suggestions for future works.| File | Dimensione | Formato | |
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https://hdl.handle.net/10589/166820